Best available copx



Nov. 20, 1928.

F. BRERO ELECTRIC IACHINE FOR WELDING METALLIC TUBES 0R PIPE l l a f m .y E 0 5 w 8 L L .1 I l llllallg. l 1 1 l |||l.. l! ZJ 6 2in1-- -L f lL r i 5 Il 9 9 A. L 2 A 1. 9%. 4 A .D au 15A 2 5 un M H 2 w f 2 H n l': n 1 w w 2 n Nov. 2o, 1928. 1,692,245

F. BRERO ELECTRIC MACHINE FOR WELDING METALLIC TUBES OR PIPES Filed Oct. 25, 1926 4 sheets-sheet 2 Nov. 20, 1928. l;692,245

F. BRERo ELECTRIC MACHINE FOR WELDING METALLIC TUBES OR PIPES Filed Oct. 25, 1926 4 Sheets-Sheet 3 Nov. 20, 1928.

1,692,245 F. BRERO ELECTRIC MACHINE FOR WELDING METALLIC TUBES OR PIPES Filed Oct. 25, 1926 4 Sheets-Sheet 4 Fig. n

.7 7a2/enfer www @fg/gw@ 2 Patented Nov. 20, 1928.

UNITED STAT-Es 1,692,245 PATENT QFFICE.

FRANCESCO BRERO, OF TURIN, ITALY.

ELECTRIC MACHINEroR WELDING METALLIC TUBES on PLPEs.

i Application med october 25, 1926, seria erally also as electrodes they are subject to a rapid/wear andtear and the work aecomlplishedby the machine is' often unsatis'fa'cto ry74 owing. to .the fact that the contact of the rollers; with the. tube to.. be Au reldedzi's n ot al- -ways uniform. Moreover. as the edgesto bef practically ne'ver he along aj l generati-ix of theftbe and, -fo rn 'a more'or less croolred'line with ,respect Ato the said generawelding. rollers, the jointgcornes'nearer gto one correspon insrgis deficientand oftenafailuref welded together the feed rollers Wholly/"independent the electric parts so thatv constructionandlongen'life.:

. lAccording to myinvention .the rollers are dividedinto two pairs, acl1` pair comprising n fiired pivot a'rolla roller mounted'upon er mounteduponatransversely moyalble pivot in order to'suit the-distances of tlie'fc'entires4 'of thecouple'of rollers tothe Slight unevennesses 1 and variations, in dimnet-erz of t fhe f tu be to be welded Whilst exertingthe pr A for feedingalongthetube.

The rollers .mounted on pivots a re actuated byfmeans of `\vorn1 s ,.t he rolleriq cominfr firstin the direction'offeedtrans- L n mitsrotation to .1

with involute teeth allowingoftheslight displacement of centers: the second roller is-not coupled with the co ed on a movable pivot which is pushed toheretofore and they .pres'sthe tubenear theV edges to be welded in exactly afradialldirec tion to the tube itself, thus avoiding friction and weer.

beinglfed. between the theycan be of.a rational,

sure necessary.

ts respective. .roller -1 1 io u nt ed o n the movablepivot byg rneans" of wheels rresponding rollerfmount? wards the former byresilient means and works essentially for guiding Athe tube, that it holds tight-directly. after welding,` When the 1 No. 144,089, and in Italy June 22., 1926.

The pressure of the electrodes cannot'bend the tube as it is exerted exactly at the point where the tube is s upported by the firstpair of feed rollers.. Moreoier, as the electrodes and rollers practically surround the whole circumference of .the tube, its heated zone will .keep exactly the desired form.

Before the electrodes and near same a devicefoi 0uiding and adjusting the direction "of the't'ule is provided, comprising a circular blade situated on the plane onivhiclrthe line fof weld shall run and two loosely mounted rollers 1for supporting the tube. Theblade lijsheld'between the edges to be welded so as to liave'thesewelded always in the middlel betwe'en thelelectrodes.

' ''.The machine is further characterized by an a i 1 tc matic hammering device 'acting upon the ltube-dir'eetly-after ts'passage between the 'eletrod.. Q ff i Y "It .fQud that hammering executed at the'metal is still it tllweliilg hatnsures Perfect- 'Connecrtionof th'eparts preventing the formation of anyporeus zones and leaving' thel'metal more Cdmpatend resistent Saftef .forging This hammering prevents moreover the formation of 'expansions along. theweldedseam.

their respecrtiye arxnsare water cooled... The el'cc-trod cfh'olders are electrically insulated from the metallic mass of the machine in =ord'e-r to fp revent this latter from working .f1.5 return. leadi "The accompanying drawing shows by wa y of exa pleaeonstrutional form of this in- 'entio n. f Figures-1 2,' 3 show' theimachine in side view,`p l aii and. front view, respectively;

i Figure is :a detailed side view toan en- I arged,

F 5 a.rear tview thereof partly in section on-line A-B of Eig. L

Figure 6 shows the'profile of the feed rollers- Figure 7`shows the'pressure device for the guide r( ll ers .v

Figures 8 and 9 are an elevation and a plan View, respectively, of the'device for guiding the tube and adjusting the line of weld in the middlebctween the electrodes.

Figures 10 and 11 show thehammering device.

i denote `a frame on the bed 2 whereofare mounted i111 the devices; viz' tivo feed rollers "l `he:pivots of the rollers and electrodes and saleofth'e tube'and current feed de- 3 and 3 actuated .through worms by a shaft 4 on which is slidably mounted a roller 5 lined with leather, receiving motion from a conical pulley 6 driven by a cone pulley 7 and pressed against the roller under the action of a balance weight 8 acting on the rocking support 9 of the pulley 6.v

The roller 5 can 'be displaced on the shaft in o rder to var jY the t-ramsmisison ratio by means of a forli 10 keyed on a rod 11 actuated by means of screw spindle and hand wheel l2.

Facing the rollers 3-3 ,are mounted the couter-rollers 13 and 13 carried on saddles 14 slida'hle between the guides 15 fixed to the bed Q. The saddles vcan Abe displaced b v meansof screw spindles and hand wheels 14 servinor also or adjusting'the lpressure on the tu e 16 clampedbetwe'en`iollers and counterrrollers.

Roller 1'3 is operatively connected with rollcrg by means oi 'two tootldiedlwheelsQti (Figs. 1 and 5) having 4the" lsame? diameter "analmente een; minder toanow a Slight displacement of the cent-resas required for adj ustingtlrepressure with which the rollers 3f-13 fact upon -thedtub'e Roller 1B is perfectly loosen The hand wheel lflt is conveniently constructed as shown in llfigure 7,

where it iscarried by .a support? 'enclosing a .2a-acting between@ shoulder 27' on e Saud 'sjprt'and a'collarlP-of the screw spindle.. ith( this' ailinge'ment the roller Y mme@ ira-guiding same fanltlessly vfithon fhind'erimr its feed even'wlnere .therear'evariations t e diameter'r other'unevenne'sse'softhe tube of which roller 13 aofilitatcsthe introduction mais 3 9 p'jpvideu with water inlet pipe 31 ad @per ourlet a8; 'orma ,pillar heads is provide an "il tank '39? ifom which a small Cfnfluitfeeds the' Oil btwen pivot and roller.

asmall zouetb'ereo o'ntlre line'o weld, upon which Artlieitioller electrode'siac t.v The machine is provided with a set of rollers for welding a correspondingset otubes o differentl diameter@- The rollerslofone set are such as to V brin'ejtle line of weld always at 'the same heighten the bed and therefore on the electrodes and othe1 devices-v as shown ldiagrammatically in Figure 6,

The saddles lflcarryingthe rollers are enasfnear as possible to each rollerslB- and 13D-1 are almosttnger'itial to each other and .tbe -welded tube leaving the former,

above which are situated the rotating electrodespromptlyreaches the second pair of rollers completing its guide and eed. A

For clearness sake the'pairsof rollers are shown on the drawing further apart from each other than they actually are.

Before the saddles 14 are situated two move .saddles 17 with guides 1S fixed to the bed 2 and moved by means ot screw spindle and hand Jwheel 19. T bese saddles carry two inclined pillars 2O supporting the arms 2,1 holding the electrodes. The arms 21 have a hollow recess 21 extending within the electrode pivots 9,12 and in which circulates the cooling water fed and discharged through the insulating tubes 22.

On pivots 212 are mounted the roller electrodes E23 the pressure ot which upon t-he tube edges 16 is adjustable by means ot adjusting screws 2l mounted in supports Q5 -fast with the pillars 2O and acting upon the arms 21.

The electrodes are constantly cleaned by brushes 33 formed by a bundle ot wires (Fig. Ll). Electric current is fed by'means of an adjustable transformer' disposed within the. bed 1 and connected to the pillars 20. The pillars and their saddles are electrically insulated from the bed 2 in order to prevent 'the metallic parts of the machine from wor'kn f1 dle 32) thus causing the roller 5 and feed rollers 3, 3 and 13 to be carried along or released.

The device for adjusting the direction of the line ofv weld shown in Figures A8 and 91 consists of two grooved rollers 40 guidingT -thertube and of a circular blade 46 held in engagement between the adjacent edges ot the tube to be welded. Therollers 40 are mount.'- ed on a base 41 at an adjustable lever on 'the bed of the machine and their pivots engage in slots 43 on the base 41 and support 42 ot the circular bladeA 46. The screws 44 and nuts 45 serve for adjusting`l the distance between 'the rollers 40. I As t e blade 46 is situated exactly on the. plane ot symmetry vet the electrodes it will keep the line'of weld constantly in thc middle between the electrodes.

The hammering device consists ot a squarcsection block 51, lodged ina forked support 52 mounted on the machine bed. The block 51 carries below a hammering tool 53 rectangular in section and is pushed downwards by a spring 54 arranged above the block in a stirrup 55 ,providedwitb a screw 5G tor adjustinjg the'springr pressure. The end of the hammc'ringtool 5? acts upon the'edges of the tube 16 directlyf aft-er the electrodes 28, when the metal is' still at the welding temperature. A pivot 59 is fast with the block 51 and carri er. -a roller '60 cooperating with a toothed wheel 61 fast with a sprocket 63 moved by the same shaft 4 as the feed rollers 3,3. As the wheel (il turns one tooth, the roller G0 (with block 5l and tool 53) is lifted and compresses the lou lill

Austing` the direction of spring 54, whereafter it falls and the tube i6 is hammered exactly in tune with its feed. rIhe intensity of hammering is adjusted by means of the set screw 56 acting upon the spring 54 and the length of the working stroke is regulated by means of a Wedge 66 cooperating with two projections 67 on the block l for determining the lowermost position of the block. The wedge 6G is guided by two grooves 68 on the stirrup 55 and is provided with a nose 66 in which engages a stud 69 for setting the wedge. Hammering can be interrupted without stopping the machine by locking the block 51 in its uppermost position by means of a brake comprising a stake 70 pushed towards the block by a spring 71 and locked by a pin 72 cooperating with the edge of the guide bushing 73.

By turning the handle 74 of the stake 70, the pin 72 is brought to correspond with a groove 75 on the bushing 7 3 so that the stake 70 snaps into a seat 76 on the block 51.

WhatIclaimis:.

1. In a machine4 for electrically Welding metallic tubes,the combination with feed rollers, roller'electrodes, and a device for adthe lineof the weld, of avhammeringdevice acting uponthe Weld- ;-ed seam directly after .the electrodes and between the feed the tube feedr :f l

2. In a machine.l for electrically welding tallic tubes,.the combination with feed rollers, roller electrodes, and a Adevice for adjusting the direction of the lline of the .weld, of a hammering device comprising ablock'movable inria support von the machine frame, a hammering tool at the end of-saidblock and adapted; to actupon' the tube edges directly.

after the 4roller electrodeSf an adjustable spring tending to lower said block, an extensionion said block,a.toothedfwheel cooperating with said extension and adaptedto lift said block, whereupon the'latter1 is freentov thefsaidA spring,

descend under the action ofy and means for .transmitting the movement from said'feed'rollers to said toothed' wheel.

3. Infa machine for .electrically weldin metallic tubes, the combination with feed rollers, roller clectrodes,andadevice foradjusting the directionof the line ofthe weld, of abanimering device'comprisingaV block movable in a support on the machine frame, a hamineringtool fat-'the'end' of said block and adapted to act upon the tube edges directly after the roller electrodes, an adjustable spring means tending to lower said block, an extension on said block, a toothed Wheel cooperating with said extension and adapted to lift said block, whereupon the block is free to descend under the action of the said spring, means for transmitting the movement from said feed rollers to said toothed wheel, and means for adjusting the limit of the downward stroke of the hammering tool.

rolls and actuated in tune with adapted to act..

4. ln a machine for electrically welding metallic tubes, (he combination with feed rollers, roller electrodes, and a device for adjusting the direction of the line of the weld, of a hammering device comprising a block movable 1n a support on the machine frame, a hammering tool at the end of said block and adapted to act upon the tube edges directly after the roller electrodes, an adjustable spring means tending to lower said block, an extension on said block, a toothed wheel cooperating with said extension and adapted to lift said block, whereupon the block is free to descend under the action ofthe said spring, means for transmitting the movement from said feed rollers to said toothed wheel, and an adjustable wedge member cooperating With projections on the block for regulating its downward stroke. Y

5. In a machine for electrieallywelding metallic tubes, the combination with feed rollers, roller electrodes, and a device for adjusting the direction of the line of the weld, of a hammering device comprising a block movable in a support on the machineframe,l a hammering tool at the end of said block and adapted to act upon the tube edges directly after the roller electrodes, an adjustable spring means tending to lower said block, an extension on said blocka toothed wheel, cooperating with said extension and adapted to lift saidbloek, whereupon the block is'free to descend under the action of thesaid spring, means for transmitting the movement from said feed rollers to said toothed wheel, and means for locking said block in its uppermost position.

l 6. In amachine for electrically welding metallic tubes, the combination with feedirollers, roller electrodes, anda-.device for adjustingthe direction of the line of the weld, of a hammering device comprising a block movable in a support on the machine framev` a. hammering tool atthe end of said. block and upon -thef` tube edges directly.. aftertheroller ,electrodes,; an adjustable spring means tendingto lower said block, an

g extension on said block, a toothed wheel cooperating with said extension and adapted to lift said block, whereuponthe block is freeY todescend under the action of the said spring, means fortransmitting themovement from said feedrollers t0 said toothed wheel, means for adjustingjthe limit of the downward stroke of the hammering tool, and means for locking said block in its uppermost position.

7. In a machine for electrically welding metallic tubes, the combination with feed rollers, roller electrodes, and a device for adjusting the direction of the line of the weld` of a hammering device comprising a block movable in a support on the machine frame, a hammering tool at the end of said block and adapted to act upon the tube edges directly after the roller electrodes, an adjustable tudinal groove on spring; means tending to lower said block, an extension on said bloc.-:, 1: toothed Wheel cooper-,il ing with said extension and adapted'to li lit said block, whereupon the block `is free to descend under the means for transmitting the movement from seid feed rollers to said toothed Wheel, 'a seat on thc block, a spring pressed etakexadapted to cooperate with said seat., a. guide bushing for said stake, piu on the stake cooperatingr 'with the edge of said guide bushingr to keep said stake in its disengaged position, and a longithe buf-:hing in which Said pin mfiy be brought/by rotating the'stake to cause the -lat-ter to snap in said seat for locking said block` 8. In a machine for electrically welding metallic tubes, two feed rollers, a worm-shaftoperatirely connected with 'the rollers, :i 'loose counter rol-lei' cooperating with one of the feed rollers, a 'counter roller geared to the other feed roller, means 'for adjusting 'the counter rollers, a change. speed gear for driving the worm sliaft comprising a roller on the` shaft., mean's for moving the roller axially of the latter, conical pulley for frictionally einfaging the roller. 'a'wei ght connectet with the pulley for coupling the 'latterl to 'the Toller,

means for'aotua'ting Ehe Weight to unco'uple the roller and pulley, radiallym'ounted roller electrodes adapted to engagez'thetub'e 'to be welded, means for -adjusti'ngfthe electrodes, guide-rolls 'for guilde-rolls for maintaining the tube in position.

metallic tubes, two feed rollers,- operatively connected with the' rollers, Ta"- loose counter roller cooperating "with 'eniefof the" feed rollers, a counter rollerggea'red 'to the other feed roller, means'fr'adjustingtlie counter rollers, 'a cliange speedZ gear for'dri'ying; the worm shaft comprisingu-roll'erfon ally of the latter, a. conica-lpulle'y'forjfrict-ionally engaging the roller, a. K veig'ht'con-j nected with the pulley for couphngfthe lat' action of the said spring,

the tube :and a disc for' engagina the edges of'the tubec'ooperating withthe -`a` Iovse" c'o'hter' 'of' the' feed rllers, abounte'roller 'geared 9. In a machine for electrically Welding a. WoIAri,1-shaft l sterft, a weighs eeneeud com-cai' puiiey for ladapted te' engage edges of the the 'guide rolls for position, 'and mechato the electrodes and the 'Welded portube cooperating with maintaining thetube 4in nis'm in close proximity feed rollers for hammering tion of the tube. Y

10. In al'macliine for electrically welding metallic tubes, two feed rollers, a wormshat operatively connected with `the rollers, aI loose counter 'roller cooperating,r ivitb one of the feed rollers, a` counter roller geared to the other feed roller, saddles carrying the 'counter-rollers, a spindle adjust-ably connected to eachl saddl*e a support 'for 'the spindle; having a shoulder't-hereinr, fa collar on the spindle, a springen the latter between the shoulder and collana 'roller on 'the worm shat,'means for'moving the roller axially of the shaft, a (xjx'lical'- pulley for frictionally v'en'g'aging; the roller?, a Weight 'connected lwith thepulley for 'coupling thela'tt-er t' the roller, means 'for 'actuating 'the Weight to luncou le the roller- 'and pulley, radially afran'geelfrdl er electrodes. for enweging the edges bf fthe' tube te be 'weide-d, iioilewf 'spinaies supporting' the eiectoesf means 'for stipp'lyirr a ilcooling medium to 'the spindles', rneans r radially adjusting the' supporting spindles, guide rolls for-Elie tube', a "di-.Sc fo1"e*ngagig fthe edgs of tl'itbe ,i end fr ie'nslA for adjusting the guide-'relirssnd' lise/11'l f- Q11. In .a machine for electrica'lylweldng mettllic tubes, j two' eed 4rollers, a `Wormshsft pertjivelycbnnectsd withuhe rollers, rel-1er cooperating with ene to the jothet feed-Toller, means for-adjusting the ente'rutters, ajrolle'f on the shaft,

:myjirventen' Ilhaye my naine. "i FRANCESCO Benno. 

